meson: use pkg-config method to find dependencies

We do not need to ask cmake for the dependencies, so just use the
pkg-config mechanism.  Keep "auto" for SDL so that it tries using
sdl-config too.

The documentation is adjusted to use SDL2_image as the example,
rather than SDL which does not use the "pkg-config" method.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

docs/devel/build-system.rst

@@ -66,46 +66,47 @@ following tasks:
    upon completion.
 
 
-Taking the probe for SDL as an example, we have the following pieces
+Taking the probe for SDL2_Image as an example, we have the following pieces
 in configure::
 
   # Initial variable state
-  sdl=auto
+  sdl_image=auto
 
   ..snip..
 
   # Configure flag processing
-  --disable-gnutls) sdl=disabled
+  --disable-sdl-image) sdl_image=disabled
   ;;
-  --enable-gnutls) sdl=enabled
+  --enable-sdl-image) sdl_image=enabled
   ;;
 
   ..snip..
 
   # Help output feature message
-  sdl             SDL UI
+  sdl-image         SDL Image support for icons
 
   ..snip..
 
   # Meson invocation
-  -Dsdl=$sdl
+  -Dsdl_image=$sdl_image
 
 In meson_options.txt::
 
-  option('sdl', type : 'feature', value : 'auto')
+  option('sdl', type : 'feature', value : 'auto',
+         description: 'SDL Image support for icons')
 
 In meson.build::
 
   # Detect dependency
-  sdl = dependency('sdl2',
-                   required: get_option('sdl'),
-                   static: enable_static)
+  sdl_image = dependency('SDL2_image', required: get_option('sdl_image'),
+                         method: 'pkg-config',
+                         static: enable_static)
 
-  # Create config-host.h
-  config_host_data.set('CONFIG_SDL', sdl.found())
+  # Create config-host.h (if applicable)
+  config_host_data.set('CONFIG_SDL_IMAGE', sdl_image.found())
 
   # Summary
-  summary_info += {'SDL support':       sdl.found()}
+  summary_info += {'SDL image support': sdl_image.found()}
 
 
 

meson.build

@@ -129,7 +129,7 @@ endif
 pixman = not_found
 if have_system or have_tools
   pixman = dependency('pixman-1', required: have_system, version:'>=0.21.8',
-                      static: enable_static)
+                      method: 'pkg-config', static: enable_static)
 endif
 pam = not_found
 if 'CONFIG_AUTH_PAM' in config_host
@@ -168,7 +168,7 @@ if get_option('xkbcommon').auto() and not have_system and not have_tools
   xkbcommon = not_found
 else
   xkbcommon = dependency('xkbcommon', required: get_option('xkbcommon'),
-                         static: enable_static)
+                         method: 'pkg-config', static: enable_static)
 endif
 slirp = not_found
 if config_host.has_key('CONFIG_SLIRP')
@@ -247,7 +247,7 @@ if sdl.found()
   sdl = declare_dependency(compile_args: '-Wno-undef',
                            dependencies: sdl)
   sdl_image = dependency('SDL2_image', required: get_option('sdl_image'),
-                         static: enable_static)
+                         method: 'pkg-config', static: enable_static)
 else
   if get_option('sdl_image').enabled()
     error('sdl-image required, but SDL was @0@',
@@ -332,7 +332,7 @@ sasl = not_found
 if get_option('vnc').enabled()
   vnc = declare_dependency() # dummy dependency
   png = dependency('libpng', required: get_option('vnc_png'),
-                   static: enable_static)
+                   method: 'pkg-config', static: enable_static)
   jpeg = cc.find_library('jpeg', has_headers: ['jpeglib.h'],
                          required: get_option('vnc_jpeg'),
                          static: enable_static)